What is the diffusion of water through a semi-permeable membrane called?

• active transport

• facilitated diffusion

• endocytosis

• osmosis

Which of the following best describes diffusion?

• the movement of a substance through a phospholipid bilayer

• the movement of a substance in water only

• the movement of a substance from high concentration to low concentration

• the movement of a substance from low concentration to high concentration

Which of the following best describes the cell membrane?

• a waterproof layer of polysaccharides connected by short chains of amino acids

• a web of protein fibers

• a bilayer of phospholipids

• a thick layer of proteins and carbohydrates

How are molecules that are too large to be moved through the cell membrane transported into the cell?

• osmosis

• exocytosis

• endocytosis

• diffusion

If the concentration of sugar is lower outside the cell than inside the cell, which of the following will happen by osmosis?

• Water will move into the cell

• Sugar will move into the cell

• Water will move out of the cell

• Sugar will move out of the cell

What type of passive transport occurs when transport proteins move sugars and other polar molecules in and out of the cell?

• endocytosis

• facilitated diffusion

• osmosis

• simple diffusion

Active transport can be used to transport substances from ___ to ___ concentrations.

• high; low

• low; high

• large; small

• equilibrium; gradient

Which of the following best describes a concentration gradient?

• the movement of substances from high concentrations to low concentrations

• a difference of in amount of particles between two areas

• the random motion of particles

• the state in which the concentrations of a substance are equal on both sides of a membrane

If a concentration gradient is present, substances will naturally diffuse from ___ concentrations to ___ concentrations.

• high; low

• low; high

• equal; low

• none of the above

Which of the following describes cell environments that are high in solutes in relation to the inside of the cell.

• hypotonic

• hypertonic

• isotonic

• prokaryotic